1 - Where are the X and Y increments located for the sprite movements of the kid, guards, jaffar, etc? I can't find them looking at the source code.
2 - I'm guessing that every sprite must have a duration to create each animation of the characters. Is this time the same for each sprite or does it change?

Nick2017 wrote:1 - Where are the X and Y increments located for the sprite movements of the kid, guards, jaffar, etc? I can't find them looking at the source code.

Take a look at seqtbl.c, which contains the sequence table. It contains the frames and X and Y increments for the animation sequences.
A pointer into this table (Char.curr_seq) is used to store the position in the animation. Every game tick, the position in the sequence table is advanced in play_seq() in seg006.c. The sequence table also contains some scripted events, such as the footstep sounds, knocking down a tile, moving to the next level on the stairs animation, etc.

However, most of the game logic is handled outside the sequence table, of course. And character displacement is also manipulated outside the sequence table in various places.